Chair



June 23, 1925. 1,543,612 J. L. ALPASCAUD CHAIR Filed Dec. 2'7, 1921 2Sheets-Sheet 1 1'1 'A Iwkewfar June 23, 1925. 1,543,612

J. L. A. PASCAUD CHAIR Filed D60- 27, 192] 2 Sheets-Sheet 2 panyingdrawings,

Patented June 23, 1925.

JULES LOUIS ADBEA PASGAUD, OF PARIS, FRANCE.

CHAIR.

Application filed December 27, 1921. Serial No. 525,218.

To all whom it may concern:

Be it known that I, JULEs LOUIS Aorta. PASCAUD, a citizen of the FrenchRepublic, residing at Paris, France, 4 Rue de Lyon, have invented a newand useful Improvement in, Chairs; and I do hereby declare the followingto be a full, clear, and exact description of the same.

This invention has for its object a chair of the invalids chair typespecially designed for enabling the user to adjust very accurately,according to his own stature and conformation, the inclination of theback, seat and legs-support of said chair so as to obtain the maximumrepose in a given time, which is not possible with the best usualpatterns of arm-chairs or invalids chairs, or even with a bed, as willbe hereinafter more fully explained.

This result may be attained by means of a device an embodiment of whichis illustrated, merely as an example, by the accent in which:

Figure 1 is a perspective side view of said chair in the position ofmaximum repose.

Figure 2 is a similar view of the same, taken from the side opposed tothat of Fig. 1 (operating hand-wheel side) one of the arm supports beingswung open in order to facilitate access to the chair.

Figure 3 is a view, on enlarged scale, in side elevation, showing t edetails of the operating mechanism, the arts of which are illustrated inthe position that they assume when the seat of the chair is initshorizontal position.

Figure 4 is a plan view of the same mechanism.

Figure 5 is a view similar to Fig. 3, but with the parts in the ositionsthat they assume when the chair is disposed so as to afford to the userthe maximum repose, the parts being locked in position.

Figure 6 is an explanatory diagram.

Figures 1 to 6 illustrate a chair enabling the user to operate thecontrolling mechanism (in order to obtain the most comfortableinclination) while lying in the chair.

As seen on the drawings, the latter comprises a pedestal A of anysuitable form chosen so as toprovide a suflicient base, a seat B, a legssupport ,0 prolonging the seat, a back D and arm supports b. 'The latter(or one of them only) may be hinged so as to enable them to be swungopen, as shown in Figure 2, in order to facilitate access to theseat B.As before stated the relative inclination of the seat, the legs supportand the back has been suitably chosen for affording the maximum reposeto the user.

The structure thus formed may oscillate upon an axle 16 carried bythepedestal.

The swinging motion of the upper part of the chair is controlled bymeans of mechanism which will now be more fully de scribed, and thedetails of which are shown in Figures 3 to'6.

Upon an axle 17 rotatable in bearings 19 fastened to side beams 6 of theseat B, is clamped an operating hand wheel 19 and a bevel pinion 2Okeyed upon the same axle meshes with another bevel pinion 21 in tegralwith a screw threaded rod 22 which rotates in a nut 23 carried betweentwo plates 24 carried in turn by a cross beam 25 of the pedestal A andprovided with two trunnions 26 slidable in elongate-d round ended slots27 in the plates 24.

It will be readily understood that rotation of the hand wheel 19 causes,through the medium of the pinions 20 and 21, rotation of the screw 22.The nut 23, hearing through its'trunnions 26, upon the station aryplates 24, causes a longitudinal displacement of the screw which resultsin an up- 8 ward or downward swinging movement of the upper part of thechair on its axle 16, according to the direction of the rotation.

When, owing to this swinging movement, the position of equilibrium isslightly assed, that is, when the vertical line passing through thecenter of gravity of the rocking structure passes slightly to the re E1of the axle 16, the locking device acts, as will be hereinafterexplained, to automatically lock the device in the best posit ion.

This locking device consists of two plates 28 capable of oscillatingaround an axle 29 carried by the plates 24. Each plate 28 is providedwith a notch 30 into which can engage one of the trunnions 27 of the nut23. A spiral spring 31 acting upon a stud 32 fastened upon one of theplates 28, tends to push the latter against the trunnions 26. So long asthe position for maximum repose is not reached, the plates 28 momentwhen the trunnions 26 and the notches 30 of the plates 28 are in thesame horizontal plane, the spring 31 will operate to engage said notchesunder the trunnions 36 and lock the system, in fixed position, as itwill be hereinafter explained.

A connecting rod 33, pivoted at 34. on the side beams 6, and having aboss 35 with an outline suitably designed for maintaining, at a giveninstant, the plates 28 far enough from the trunnions 26 to disengage thelatter'from the notches 30 rest on its edge upon an anti-friction roller36 mounted on an axle 37 interconnecting the plates 28. The boss isprolonged by a tapering part 38.

The mode f operation and the functioning of this improved chair, is asfollows The seat B being assumed, at the beginning, to be placedhorizontally and the various parts of the mechanism in the positionsshown in Fig. 3, the person who desires to rest (hereinafter referred toas the user) swings open one of the arm rests b, as shown in Fig. 2,lays himself upon the cushions C B and D, while taking care to bring hisbody thoroughly into contact with the two latter, and raises the armrest I) back into place.

Then with his right hand, the user rotates the hand wheel 19 in thedirection indicated by the arrow, which rotation results, as aforesaid,in causing the seat B to oscillate slowly upwards on its axle 16, thetrunnions 26 which, during this movement, bear upon the lower ends ofthe stationary elongated slots 27 (Fig. 3), opposing the movement fromleft to right which the spring 31 would impart to the plates 28, if theydid not abut against these trunnions.

At a given moment, the osition of unstable equilibrium, indicate by dashand dot lines in Figure 5, is reached and then slightly passed, and thewhole movable part of the chair under the influence of its own weightand that of the user, begin to oscillate rearwardly on the axle 16. Thisoscillation, of very small amplitude, stops almost immediately, that is,as soon as the trunnions 26 (carried along upwards with the nut 23 andthe screw 22), after having left the lower ends of the slots 27, abut,as shown in Fig. 6, against the upper ends of the slots. At this moment,the user feels a very slight shock warning him that the position ofmaximum repose has been reached and that he no longer needs to rotatethe hand wheel 19.

The width of the connecting rod 33 is chosen so that, whatever be theprecise instant when this slight oscillation takes place (said instantbeing dependent on the weight and form of the user and, consequently,variable according to the user), at this instant the boss 35 has amplypassed the roller 36, thus opposing to the same only its sufilcientlynarrowed end 38 (Fig. 5).

Just at the moment when the trunnions 26 have moved upwards, the plates28, yielding to the spring 31, oscillate from left to right, theirnotches 30 engaging under the trunnions 26 and locking them, without anyplay in the upper ends of the slots 27, so that the chair becomes firmlylocked in its best position (indicated by full lines in Figure 5) andcannot rock on its axle 16, in case the user brings the upper part ofhis body forward. I

For bringing the seat B back to the horizontal position, it suffices torotate the hand wheel 19 in the direction opposit to that indicated bythe arrow, so as to cause said seat to oscillate forward and downwardson the axle 16. The position of equilibrium is again reached, then theweight is brought forward, the vertical line passing through the centerof gravity of the massconstituted by the upper: part of the chair and bythe user now passing through the interior of the triangle of supportformed by the two pivots and the screw 22. The trunnions 26, due to thisweight tends to move down- Wards, but remains stationary, being clampedin the notches 30 of the plates 28, until the boss 35 of connecting rod33, which descends together with the seat, comes into contact with theroller 36 and gradually pushes plates 28 from right. to. left. Thenotches 30 then liberate the trunnions 26, which, being already urged bygravity, fall to the bottom of the slots 27 to-the position shown inFig. 3. There results "a slight swinging movement, in a directionreverse to the preceding one, and felt by the user. By further rotatingthe hand wheel 19 still in the same direction, the seat B is returned tothe horizontal position. The user in getting up from the chair, then hasmerely to swing open one of the arm rests b.

The engagement and disengagement of the mechanism is thus efiected, asseen from the foregoing explanations, in two quite distinct successivestages, i. e., in the first case, limited rearward swinging movement ofthe seat B, then locking of the plates 28, and in the second case,disengagement of the trunnions 26 from the notches 30 of the plates 28owing to the intervention of the boss 35 of the connecting rod 33, andthen limited forward swinging movement of the seat B. The first limitedswinging movement has for its purpose to warn, by the aforesaid verylight shock, that the chair is reaching the position of maximum repose.v

Though the inclination of the several arts of the chair be determinedonce for all by the manufacturer of the same, said parts may beconstructed so as to be detachable from each other or capable of beingfolded upon each other, in view offacilitating transportation of thechair.

Notwithstanding the very great simplii ity 1. A chair of the invalidschair type for securin maximum re ose com risin a 3 &7

seat having arms, a back, and a leg rest.

attached thereto, a supporting pedestal, a pivot rockingly connectingthe rear lower edge of the seat. to the pedestal, a hand operated screwmechanism for Varying the inclination of the seat, an automatic lockingdevice for locking the seat in fixed position, after it has been rotatedrearwardly on its axis beyond its point of equilibrium, said screwmechanism including slotted plates attached to the pedestal, a nuthaving trunnions slidable in the slots of the plates, a threaded shafthaving one end received in the nut, and gears connecting the other endof the shaft to the seat.

2. A chair of the invalids chair type for securing maximum repose,comprising, a

seat having arms,-a back, and a leg rest attached thereto, a supportingpedestal, a pivot rockingly connecting the rear lower edge of the seatto the pedestal, a hand operated screw mechanism for varying theinclination of the seat, an automatic locking device for locking theseat in fixed position, after it has been rotated rearwardly on its axisbeyond its point of equilibrium, said pivot rockingly connecting therear lower edge of the seat to the pedestal, a hand. operated screwmechanism for varying the inclination of the seat, an automatic lockingdevice for locking the seat in fixed position,

after it has been rotated rearwardly on its axis beyond its point ofequilibrium, said screw mechanism including slotted plates attached tothe pedestal, a nut having trunnions slidable in the slots of theplates, a threaded shaft having one end received in the nut, and gearsconnecting the other end of the shaft to the seat, said automaticlocking device including pivoted, notched, spring pressed platesassociated with the pedestal, a roller pivoted between the plates,

and a cam arm pivoted to the seat and posi-' tioned to operate theroller and the spring pressed plates, the notches in the plates coactingwith said trunnions.

4. A chair of the invalids chair type for securing maximum repose,comprising, a seat having arms, a back, and a leg rest attached thereto,a supporting pedestal, a

pivot rockingly connecting the rear lower edge of the seat to thepedestal, a hand operated screw mechanism for varying the inclination ofthe seat, an automatic locking device for locking the seat in fixedposition, after it has been rotated rearwardly on its axis beyond itspoint of equilibrium, said screw mechanism including slotted platesattached to the pedestal, a nut having trunnions slidable in the slotsof the plates, a threaded shaft having one end received in the nut, andgears connecting the other end of the shaft to the seat, said automaticlooking device including pivoted, notched, spring pressed platesassociated with the pedestal, a roller pivoted between the plates, and acam arm pivoted to the seat and positioned to operate the roller and thespring pressed plates, the notches in the plates coacting with saidtrunnions, the pivoted plates being pivoted on the slotted plates, thenotches in the pivoted plates receiving the trunnions of the nut to lockthe chair in its position for repose, the cam arm automaticallycontrolling motion of the notched plates, as the chair pivots on thepedestal, by moving the roller and therewith the pivoted plates.

In testimony whereof, I have signed my name to this specification. Y

Dr. JULES LOUIS ADREA PASCAUD.

